A typical recessed hinge has two hinge parts adapted to be recessed, one in a door frame and one in an edge of a door panel. A link assembly extending between the hinge parts allows the door to pivot in the frame about a vertical axis, frequently through an angle of up to 180°. When the door is closed, such a hinge is normally completely concealed.
At least one of the hinge parts is provided with a mechanism that allows the hinge to be adjusted in three mutually perpendicular directions, that is front-to-back horizontally perpendicular to the vertical plane of the door frame, horizontally side-to-side parallel to this plane and perpendicular to the vertical pivot axis of the hinge, and vertically parallel to the hinge pivot axis. This way the door can be perfectly centered in the frame and, with the front-to-back adjustment, the amount of compression of a seal in the frame can be controlled. When at least two such hinges are provided with their pivot axes coaxial, it is also possible to ensure that the door is perfectly vertical or, if a closing or opening movement is desired, at a slight angle to the vertical.
Such a hinge that is fully concealed between the frame and the door when the door is closed and not visible on the outside of the door is typically used for doors for residential and office spaces as well as interior and exterior building doors. The doors may have considerable weight, and therefore the door hinges and their components must meet stringent requirements for dimensional stability and continual load. In principle, the hinge system is also usable for windows and other building closures.
Normally one of the hinge parts of this invention allows vertical adjustment of the door relative to the frame and also a front-to-back compression adjustment of the door whereas the other can be responsible for the other horizontal adjustment parallel to the door plane. The vertical adjustment as well as the compression adjustment of the door are of crucial importance for doors equipped with a recessed door hinge. For design reasons, recessed door hinges are frequently used in doors whose doors end in flush alignment with the door frame, with a reveal remaining between the door and the door frame. The door must be adjusted in such a way that the reveal has constant dimensions over the entire periphery of the door in the closed state. Even minor deviations are perceived as having an extremely unattractive appearance. The compression adjustment of the door as well as the vertical adjustment of the door must therefore work with high precision. During adjustment, the entire weight of the door must be borne by the hinge structure in order to precisely adjust the door position. After adjustment, all mutually movable parts must be fixed connectable to one another so that the door does not shift, even under continual load.
A hinge part for a recessed door hinge for doors is known from WO 2015/149495. It has a housing for fastening to a frame or door, a support body adjustably mounted in a cavity of the body, and a bearing block for connecting links of the link assembly. The bearing block has a rotatable pinion meshing with teeth on the support body, thus allowing a horizontal adjustment of the bearing block. Vertical adjustment of the door hinge is provided on another separate hinge part.
A recessed-mount door hinge between a door frame and a door is also known from U.S. Pat. No. 6,829,808. This door hinge also has a first hinge part and a second hinge part joined together by a link assembly. The two hinge parts are insertable into mortises in the door frame and in an edge of the door. Each of the two hinge parts has a housing for fastening to a frame or a door and bearing blocks for connecting links of the link assembly. Each of the bearing blocks of the first hinge part is vertically adjustable in a guide recess in the respective housing. The bearing blocks of the other hinge part are horizontally adjustably mounted in the respective housing. Adjusting eccentrics are provided for the horizontal adjustment as well as for the vertical adjustment. It is disadvantageous that the vertical adjustment and the lateral adjustment of the door must be carried out on different hinge parts. In addition, the precision of the adjustment, in particular the compression adjustment of the door, is still in need of improvement.